TRANSFER CASE DIAGNOSTIC AND EXCHANGE PROCEDURE

Model and Year: 1989 K3 TRUCK

TO: ALL CHEVROLET DEALERS

THIS BULLETIN COVERS:

Preliminary diagnosis and exchange procedure for the 1370 Transfer Case.

Until further notice, ANY 1370 Transfer Case needing repair will be exchanged for a new unit. A copy of this bulletin should be filed in your dealership "Special Exchange Policy Binder" previously provided.

SERVICE INFORMATION:

Preliminary Diagnosis Procedure:

- Insure that the clutch coil relay (mounted to the cowl, under the hood) is present and properly mounted. Refer to Section 7D of the Service Manual.

- Refer to the Service Manual Diagnostic Charts.

- Insure correct oil fill.

- Insure the transfer case shift linkage is properly adjusted.

- Insure the shift linkage is free and not blocked by the wiring cable.

- Insure all wiring connections are making good contact and are properly seated.

- Insure all engine and transmission mounts are tight.

- Check for proper tire inflation.

EXCHANGE PROCEDURE:

1. Reference Figures No. 1 and 2, and have information available before calling. If the vehicle has an oil leak, determine where the leak is by using the oil leak identification chart. The noise and shifting charts can be filled out by using check marks. It is necessary to record this information as it will be needed to fill out the form on the transmission being returned. (Blank forms will be shipped with exchange unit.) Record the GM part number, the Borg-Warner part number, and the unit serial number from the I.D. tag located at the rear of the transfer case.

2. Call Chevrolet Technical Assistance, TAN will arrange with Borg-Warner Automotive to ship an exchange unit within one working day (24 hours).

3. Technical Assistance will provide an authorization number. This number must be written on the transfer case in black marker before its return. If the case is excessively greasy, write the authorization number on a tag and attach it to the case with wire.

4. Once an exchange unit is received, the replaced unit is to be returned to Borg-Warner Automotive within 8-10 days to avoid a chargeback. A return shipping label will be sent with the exchange unit.

5. The replaced unit MUST be returned complete as removed from the vehicle without examination of the unit. Dealerships returning units even partially disassembled (excluding removal of shift lever linkage during removal of the unit), will be subject to being billed for materials furnished.

6. The exchange unit will have a plastic bag attached to it. This bag will contain:

Return shipping labels

Reporting form

Return shipping carrier information

Identification tag

Leak identification chart

PREPARATION FOR SHIPPING:

1. Drain all oil from unit.

2. Remove all plastic shipping plugs and covers from the replacement unit and install them on the replaced unit.

3. Place the report form, the identification forms, and a copy of the work order in the enclosed plastic bag. Attach the bag and the identification tag to the complaint unit with enclosed wire.

4. Write the authorization number on the case cover on the complaint unit.

5. Repack the replaced unit into the original shipping container.

6. Place the shipping label on the original shipping container.

IMPORTANT: All return shipping is COD to Borg-Warner. Exchange units are complete less shift tower and linkage.

WARRANTY INFORMATION:

For repairs performed under warranty, claims may be submitted for R&R labor, Dextron 11 fluid, and miscellaneous parts, if required. Replacement transfer cases will be shipped to the dealer on a no-charge basis.

For vehicles repaired under warranty, use:

Labor Op: K4410 Labor Time: 1.3Hrs

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.